[unreadable] MagneSensors' program is aimed at developing a nanotechnology platform that uses ultra-sensitive magnetic sensors and magnetic labels to perform powerful new cell assays on live cells. This magnetic detection platform uses high temperature (high-Tc) superconducting quantum interference devices (SQUIDs) to detect the magnetic field generated by biomolecules tagged with magnetic nanoparticles. The Phase I effort is specifically aimed at employing innovative nanotechnology to reduce and control critical dimensions in magnetic sensors and magnetic nanoparticle labels to drive next generation instrumentation and then demonstrating applicability in sensitive cell assays. Phase I uses model systems for proof-of-concept cell assays. Cell assay specific aims include: 1) detection of cell surface receptors (ICAM-1) on 100 adherent live cells (HUVEC), 2) detection of cell surface receptors (Ig) on 10 non-adherent live cells (CRL-1923), and 3) detection of 50 "rare" B cells in a background of 10,000 "normal" T cells. Smaller (10-20 nm) active devices to improve the magnetic sensors, and small (30-80 nm), more uniform, and more powerful magnetic nanoparticles are required to further push the instrument sensitivity towards the ambitious Phase II goals of single cell detection and rare cell detection. The benefits of the new cell assays include: a) the sensitive detection of rare cells within a "normal" cell population (such as fetal cells in maternal blood, metastatic tumor cells, infected host cells), b) ultra-sensitive "mix and measure" assays on cell surface receptors or proteins capable of being performed on a finger stick of blood and no sample preparation. The latter could eventually replace cell culturing for the rapid detection of infections (e.g. sepsis and septic shock) where an immediate answer is needed and delay can prove fatal. This "nanobiotechnology" program will benefit from the close interdisciplinary collaboration of an experienced group of physicists, chemists, and biologists. [unreadable] [unreadable]